Vibration 2

Practical Vibration Analysis: Solutions to Machine Problems

Level II Certification Available

Since Update International started teaching vibration analysis in the mid ‘60s, we have always kept our focus on giving practical information. Our years of training experience have given us insights into how to get concepts across in a truly effective manner. To enhance the learning experience we have added our unique computer based learning environment to the seminar. This allows some “hands-on” type experiences and practice sessions to the classroom training. Using the vibration simulator, self-paced practice ‘homework’ will allow the students to get practice using the concepts they learn in the classroom right away.
In addition, we now bring machines into the classroom along with our virtual instruments in order to create hands on experiences for each participant. This includes taking routes and off- route measurements, recognizing alert and alarm levels, doing basic analysis and using special techniques such as FRR tests and 10 division plots.

Update International has always taught analysts to determine the causes of vibration problems and eliminate them, not only making “bad” machines into OK machines, but also making OK machines into precision machines. In recent years, we have gone even further by making the goal to eliminate the problems before the machine is turned over to operations – before they do damage to the machine.

We begin the seminar with introducing the course instructor and the attendees (their backgrounds and goals for the seminar), who are all encouraged to share their experiences to add to the knowledge being offered. The philosophies of maintenance are discussed as a vibration program must work within that program and cannot be separate from the overall maintenance program.

Next is an overview of the major condition monitoring technologies: infrared, ultrasonic, oil analysis, wear particle analysis and motor current signature analysis. The emphasis is on how these technologies can complement vibration analysis for a more effective program.

After a discussion on the different types of monitoring (such as periodic and constant) a brief history of vibration analysis is given. We then look at the various components of a monitoring program, from routes to reports. In order to understand the system the class will load a database with some history take measurements on a route, recognize which points are in alarm and examining trends.

The different types of amplitude measurements and when to use them are introduced. History is often a neglected area which reflects a communication gap in the plant. We address this concern throughout the seminar as it is a very important element in an effective program. The concept of amplitude analysis (comparing amplitudes at various positions and directions) is demonstrated and practiced. Even at this early stage the concept of resonance is introduced, as it can affect even the most basic analysis.

A generic overview of the types of vibration instruments and transducers is covered. The emphasis with transducers will be on proper mounting techniques. Each student will take measurements on the practice machines using different mounting techniques. We will be using Update’s virtual instrument to demonstrate in the classroom but only the generic concepts, applicable to all instruments, will be taught. The primary focus is on the setting and parameters that must be addressed with each instrument, such as resolution, low frequency cutoff and sampling rate.

The introduction of waveforms and spectra are shown with hands on exercises on the simulator. Frequency analysis is then introduced with a unique understanding. At the same time we can lay a foundational understanding of the concept of phase. The limitations of some of the rules of thumb that many heavily rely on are explained with an understanding of vectors.

Beginning spectral analysis starts with definition of terms and clearing up common misconceptions. An overview shows what symptoms show up in each area of a spectrum. What can create vibration at frequencies less than 1x RPM, at running speed, in the lower harmonics, and at higher frequencies. This will show the typical pattern for most vibration problems. We will discuss the mental approach to a vibration analysis in order to have a strategy for analyzing a vibration problem.

The most common distinction that the analyst will have to make is that of separating imbalance from misalignment. This task is practiced through hands on exercises.

An overview of the different types of alarms is covered followed by taking measurements on the machines and comparing them to alarm levels.

Resonance is a major concern for the vibration analyst as there are usually more machines with at least a partial resonance amplifying vibration a source. While the concept of resonance is introduced earlier, this is the point where it is studied further. A number of very effective, practical techniques for detecting and eliminating resonance can be performed by non-analysts (such as mechanics and operators) with just minimal training. Again, case histories add to the student’s knowledge.

Three very important concepts need to be understood in order to do effective analysis without confusion. Truncation of a waveform which creates harmonics in a spectrum, modulation of a waveform which creates sidebands in a spectrum, and beats, created by two frequencies going in and out of phase with each other. Knowing why these occur will provide a better understanding of the conditions that produce symptoms.

The final morning will include discussions on bearing failure stages, vibration reports, and a review of the concepts covered in the course. This is to reinforce and practice the many concepts and techniques learned during the week.

This brings us to about noon on the last day. The afternoon is reserved for those who wish to take the optional certification test.Who Should Attend:

Maintenance and Reliability Engineers

Vibration Specialists

Advanced Mechanical Technicians

Notebook/Laptop Computer

This seminar uses vibration analysis simulation software. We recommend that you bring a notebook computer to the seminar.